Thesis (Ph. D.)--Washington State University, May 2010. / Title from PDF title page (viewed on June 10, 2010). "Department of Civil and Environmental Engineering." Includes bibliographical references.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves 71-72). Also available in electronic version.

Thesis (Ph. D.)--University of Canterbury, 2007. / Typescript (photocopy). "January 2007." Includes bibliographical references. Also available via the World Wide Web.

Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). "February 2008." Includes bibliographical references (p. 191-199). Also available via the World Wide Web.

Organosilanes are widely used to bond organic materials such as polymers to inorganic materials in polymer composites. However, the mechanism of adhesion is poorly understood. One postulated mechanism is the interdiffusion of the silane and polymer, along with condensation of the silane to form an interpenetrating polymer network (IPN). The techniques of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and Raman confocal microscopy have been used to study the diffusion, hydrolysis and condensation of three organosilanes in silicon / PVC / silane laminates. These processes are thought to contribute to the formation of the IPN, and hence to be vital for adhesion. The organosilanes studied were [3-(amino)propyl]trimethoxysilane, also known as A1110, [3-(phenylamino)propyl]trimethoxysilane, known as Y9669, and [3-(mercapto)propyl]triethoxysilane, known as A1891.ATR-FTIR was shown to be an excellent technique for studying the kinetics of silane diffusion through PVC films. It was shown that at room temperature, no diffusion through unplasticised PVC films occurred. At 70 °C, however, diffusion occurred readily for Y9669 and A1891. In plasticised PVC films, diffusion was observed for all three silanes at room temperature. It was shown that the diffusion occurred more quickly with higher plasticiser concentrations, and hence lower glass transition temperatures. The kinetics of diffusion was found to fit a dual mode sorption model. Hydrolysis of the silanes was also followed by infrared spectroscopy, and the kinetics of hydrolysis and condensation were shown to be highly dependent upon silane type, the concentration of water, and the presence of an acid catalyst. The hydrolysis of the silanes was found to slow their diffusion through both plasticised and unplasticised PVC films. It was shown that the presence of water in the films caused the hydrolysis of the silanes in situ. Raman depth profiles were measured of the films before, during and after diffusion. The spatial resolution was shown to be adversely affected by refraction at the air / PVC interface. It was shown that it is possible to deconvolve the confocal response of the microscope from the depth profiles, resulting in greater spatial resolution. Hydrolysis of the silanes was followed in solution by Raman spectroscopy, and it was found that each of the three silanes showed different rates of hydrolysis and condensation. It was shown that it was also possible to follow the kinetics of diffusion by Raman microscopy, and the results agreed well with those shown by ATR-FTIR spectroscopy.

The growing use and demand for microwave communication systems has led to an increase in system density, particularly in urban areas. Consequently this rise has increased the risk of interference. Especially in urban areas the abundant presence of potential obstacles increase the risk of multipath propagation. Multipath propagation on radio links is associated with signal delays and signal level fades on which adversely influences the system performance. For efficient frequency planning the knowledge of the multipath geometries involved is required. This knowledge can be obtained by resolving the experienced multipath field into its constituent components yielding their amplitudes and angles of arrivals at a receiver terminal. Some previous investigations into the resolution of multipath generated height gain curves are documented in the literature. These generally however oncentrate on resolving the two predominant signal components. In an urban environment the number of expected constituent signal components exceed the number of two. Resolution of more than two components requires considerably more effort than this relatively simple case. This thesis provides a component resolution procedure which determines the individual amplitudes and angles of arrival of constituent multipath components. The procedure is applied to the spatial amplitude envelope observed when displacing a receiver incrementally over a distance of a few wavelength through a multipath field. The presented solution can be applied with inexpensive easurement and computational means. For the resolution process it is only required to record the envelope pattern amplitude values without any phase information being required. The use of a single standard antenna as receiver is also sufficient. The procedure does not require data of an array of antenna elements. The performance of the resolution procedure has been tested and validated in an extensive experimental programme which was part of this research. Preliminary results of this project are published in the report of the European COST 235 project.

A análise harmônica e o ramo da matemática que estuda a representação de funções ou sinais como a sobreposição de ondas base. Ela investiga e generaliza as noções das séries de Fourier e da transformação de Fourier. Neste trabalho, investigou-se um teorema de restrição da transformada de Fourier devido a Mitsis e Mockenhaupt (uma generalização do teorema de Stein-Tomas). Foram realizados estudos analíticos sobre o método para operadores integrais oscilatórios, baseado na fase estacionária. Os resultados permitem deduzir o teorema de restrição no plano (em seu caso geral) e o teorema de Carleson-Sjölin. / Harmonic analysis is the mathematical branch that studies the function or signals representation as a base wave overlay. It investigates and generalizes the notions of Fourier series and of the Fourier transform. In this work, was investigated a restriction theorem of the Fourier transform due to Mitsis and Mockenhaupt (a generalization of Stein-Tomas theorem) . Were performed analytic studies on the method for oscillating integral operators, based in the stationary phase. The results allow deducing the restriction theorem on the plane (in the general case) and the Carleson-Sjölin theorem.

A análise harmônica e o ramo da matemática que estuda a representação de funções ou sinais como a sobreposição de ondas base. Ela investiga e generaliza as noções das séries de Fourier e da transformação de Fourier. Neste trabalho, investigou-se um teorema de restrição da transformada de Fourier devido a Mitsis e Mockenhaupt (uma generalização do teorema de Stein-Tomas). Foram realizados estudos analíticos sobre o método para operadores integrais oscilatórios, baseado na fase estacionária. Os resultados permitem deduzir o teorema de restrição no plano (em seu caso geral) e o teorema de Carleson-Sjölin. / Harmonic analysis is the mathematical branch that studies the function or signals representation as a base wave overlay. It investigates and generalizes the notions of Fourier series and of the Fourier transform. In this work, was investigated a restriction theorem of the Fourier transform due to Mitsis and Mockenhaupt (a generalization of Stein-Tomas theorem) . Were performed analytic studies on the method for oscillating integral operators, based in the stationary phase. The results allow deducing the restriction theorem on the plane (in the general case) and the Carleson-Sjölin theorem.

The aim of this work was to assess the potential of FTIR spectroscopy in the analysis of the cis and trans fatty acid contents of fats and oils. Preliminary studies on the liquid and solution phase spectra of individual FAME'S (fatty acid methyl esters), and on mixtures of FAME'S, were conducted to establish whether spectral features enhanced by FTIR could be used to provide improved methods of determining cis and trans contents. A number of previously unreported bands and spectral features associated with the cis and trans isolated double bond(s) were discovered. None of the trans bands were considered suitable for quantitation, however, methods of determining the cis content were developed, based on the the two bands listed below. These methods were compared with current IR methods, and with a capillary GC method. (a) The CIS C=C stretching band (1654 cm-1). (b) An unassigned band at 913 cm-1, observed only in the spectra of non-conjugated di- and tri-unsaturated FAME'S. All the established methods as well as those developed in this work, for the quantitative analysis of FAME'S have inherent disadvantages. For example, with the capillary GC method, difficulties are encountered in resolving and identifying samples containing complex mixtures of isomers. With the IR techniques, the difficulties involve the elimination of interfering bands, and the absorbance of similar fatty acids at the same frequencies. The application of GC-FTIR was seen as a logical extension of this project, because it offered a great potential for the separation and charactisation of components of complex mixtures. Studies conducted on vapour phase spectra showed that the identification of many FAME'S could be ascertained from various band ratios. Furthermore, band ratios could be used to quantify the cis/trans content of co-eluting isomers. Different types of capillary columns were tried, and optimum conditions established where possible.

The discrete Fourier transform in Cartesian coordinates has proved to be invaluable in many disciplines. However, less theory has been developed for functions that are best described in polar coordinates. In this thesis, a new discrete 2D-Fourier transform in polar coordinates is proposed and tested by numerical simulations. Guidelines for choosing sample size are developed. Furthermore, to be as useful as its Cartesian counterpart, improvements are made to reduce the computing time.